Prevalence, Antimicrobial Susceptibility Patterns, and Risk Factors for Staphylococcus aureus from Meat of Animal Origin in Mekelle, Tigray, Northern Ethiopia

Background: Staphylococcus aureus (S. aureus) is well known for causing human and animal diseases, primarily through the consumption of contaminated meat.

Objective: This study aimed to determine the presence of S. aureus, its antimicrobial susceptibility test, and risk factors from meat of animal origin in Mekelle, Northern Ethiopia.

Method: Socio-demographic data were collected using a pre-designed questionnaire. Meat samples were collected sterilely from butchers and abattoir facilities and transported in an icebox to the microbiology laboratory. An isolation, characterization, and antimicrobial susceptibility test was performed using the disc diffusion method. The data were cleaned and entered into STATA 20.0. Logistic regression models with odds ratios were used to assess risk factors and bacterial contamination. A p-value of < 0.05 was considered statistically significant.

Results: During the current investigation, we collected 250 samples. The analysis revealed the presence of contamination by S. aureus in 88 (35.2%) of the samples. The prevalence of S. aureus in samples from the butcher and abattoir houses was 37.6% (n=47) and 32.8% (n=41), respectively. Significant factors included, use of gloves (COR = 0.523; 95% CI: 0.308-0.889, P-value: 0.017, AOR = 0.222; 95% CI: 0.104-0.473, P-value: 0.001), strict separation between clean and dirty areas (COR=2.48; 95% CI: 1.45-4.24), and poor handwashing practice (COR=2.93; 95% CI: 1.41-6.06), with all associated with S. aureus contamination. The presence of resistance to cefotaxime, ampicillin, and penicillin G was observed in all isolates of S. aureus from butcher and abattoir house sources. In contrast, the in vitro antimicrobial sensitivity pattern of amikacin, cephalexin, gentamicin, trimethoprim-sulfamethoxazole, and nitrofurantoin was tested.

Conclusion: This study highlights the widespread presence of S. aureus in meat products. Consequently, early identification of the pathogen and antimicrobial susceptibility testing for S. aureus are crucial to improve treatment outcomes and prevent the development of drug resistance.